Abrasive tool



March 10, 1942. A. K. JOHNSON 2,275,766

'ABRASIVE TOOL Filed June 12, 1941 ATTORNEY Patented Mar. 10, 1942 UNlTED TE ABRASIVE TOOL Alfred K. Johnson, Chicago, Ill. Application June 12, 1941, Serial No. 397,673

'7 Claims.

The invention relates to improvements in abrasive tools especially adapted for sharpening skates or the like and has for its primary object the provision of an improved tool of the character indicated which is capable of economical production and highly efficient in use.

Other objects will appear hereinafter.

The invention consists of the combinations and arrangements of parts hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawing forming a part of this specification and in which Fig. 1 is a side view of the tool embodying the invention;

Fig. 2 a partial vertical longitudinal section of the same;

Fig. 3 a section taken substantially on line 3-3 of Fig. 2;

Fig. 4 a view similar to Fig. 2, on a smaller scale and showing a slightly modified form of construction; and

Fig. 5 a section taken substantially on line 5-5 of Fig. 4.

The embodiment of the invention illustrated in the drawing comprises a flexible tubular abrasive member If! preferably formed from a sheet of emery cloth or the like having its edges overlapped and adhesively secured together at H as shown in Fig. 3. Wedges l2 and I3 are arranged as shown to be inserted within the memv ber l0 to stretch the same when said wedges are forced together, the wedge l3 being made longer than the wedge I2 to facilitate such a stretching action and also the removal of the wedges as will be readily understood. In this way the abrasive member ID is stretched so taut as to be comparable to a sharpening stone. The outer edges I4 and 15 respectively of the wedges l2 and I3 are rounded as indicated and said wedges are transversely tapered so that the edge 14 is materially smaller than the edge l5 as shown in Fig. 3 thereby giving the assembly substantially the shape of a slip stone, known to the trade as such.

By this arrangement an abrasive tool is provided which is especially adapted for sharpening or polishing the bearing edges of ice skate runners. In use the tool is held in the hand with the thumb or one finger projected beyond one rounded edge and applied to the edge of the skate runner with the projecting thumb or finger rubbing against the side of the runner to serve as a guide for such application. By making the edges of the Wedges rounded and of different sizes the tool is adapted for use on runners having different sizes or different degrees of curvature in their cutting or bearing edges. When one portion of the abrasive member becomes worn the same may be readily shifted in position on the tool by releasing and inserting them in a slightly different relation or position as will be readily understood. In this way when the sheet Iii becomes worn the same may be readily shifted so as to bring fresh abrasive overthe edges of the tool and thereby avoid any distortion in shape as results where a stone is used.

In the modified form of construction illustrated in Figs. 4 and 5 three wedge members, instead of two are employed as indicated. Wedge members I2 and I3, corresponding to wedge members l2 and I3, except that they are slightly smaller, are arranged to cooperate with a central longer wedge member It as shown. The operation is substantially the same as before.

While the preferred form of construction has been illustrated and described this is capable of variation and modification without departing from the spirit of the invention. It is therefore not desired to limit the patent to the precise details disclosed, but to include also such variations and modifications as fall within the scope of the appended claims.

I claim:

1. An abrasive tool comprising a flexible tubular abrasive member; and cooperating wedges insertable therein to stretch the same.

2. The construction specified in claim 1 in which one of said wedges is longer than the other. I

3. The construction specified in claim 1 in which the outer edges of the wedges are rounded.

4. The construction specified in claim 1 in which the outer edges of the wedges are rounded and one made larger than the other, and one of said wedges is longer than the other.

5. The construction specified in claim 1 in which the tool is provided with two tapered edges.

6. The construction specified in claim 1 in which the two cooperating wedges are employed for stretching the abrasive member.

7. The construction specified in claim 1 in which three cooperating wedges are employed for stretching the abrasive member.

ALFRED K. JOHNSON.

the wedge members 

